From b7ac9e4a85a6060ef97d31cd6b8ea936e93ebcb8 Mon Sep 17 00:00:00 2001
From: teodosii <rares.mardare@grafana.com>
Date: Tue, 20 Dec 2022 11:22:41 +0200
Subject: [PATCH] basic test for faro

---
 grafana-plugin/src/utils/faro.test.ts | 84 +++++++++++++++++++++++++++
 grafana-plugin/src/utils/faro.ts      |  4 +-
 2 files changed, 87 insertions(+), 1 deletion(-)
 create mode 100644 grafana-plugin/src/utils/faro.test.ts

diff --git a/grafana-plugin/src/utils/faro.test.ts b/grafana-plugin/src/utils/faro.test.ts
new file mode 100644
index 00000000..04bb93de
--- /dev/null
+++ b/grafana-plugin/src/utils/faro.test.ts
@@ -0,0 +1,84 @@
+import FaroHelper from 'utils/faro';
+
+import 'jest/matchMedia.ts';
+
+import { describe, test } from '@jest/globals';
+import '@testing-library/jest-dom';
+
+jest.mock('@grafana/faro-web-sdk', () => ({
+  initializeFaro: jest.fn().mockReturnValue({
+    api: {
+      pushLog: jest.fn(),
+    },
+  }),
+  getWebInstrumentations: () => [],
+}));
+
+jest.mock('@grafana/faro-web-tracing', () => ({
+  TracingInstrumentation: jest.fn(),
+}));
+jest.mock('@opentelemetry/instrumentation-document-load', () => ({
+  DocumentLoadInstrumentation: jest.fn(),
+}));
+jest.mock('@opentelemetry/instrumentation-fetch', () => ({
+  FetchInstrumentation: jest.fn(),
+}));
+
+describe('Faro', () => {
+  const OLD_ENV = process.env;
+
+  beforeEach(() => {
+    jest.resetModules();
+    process.env = { ...OLD_ENV };
+  });
+
+  afterAll(() => {
+    process.env = OLD_ENV;
+  });
+
+  const getProcessEnv = (
+    config: { faroUrl?: string; apiKey?: string; enabled?: string } = {
+      faroUrl: 'localhost:12345/collect',
+      apiKey: 'secret',
+      enabled: 'true',
+    }
+  ) => {
+    const { faroUrl, apiKey, enabled } = config;
+
+    return {
+      FARO_URL: faroUrl,
+      FARO_API_KEY: apiKey,
+      FARO_ENABLED: enabled,
+    };
+  };
+
+  test('It initializes faro ENABLED === true', () => {
+    process.env = getProcessEnv();
+    const faro = FaroHelper.initializeFaro();
+
+    expect(faro).toBeDefined();
+    expect(faro.api.pushLog).toHaveBeenCalledTimes(1);
+  });
+
+  test('It does not initialize faro if ENABLED != true', () => {
+    process.env = getProcessEnv({ enabled: 'some-other-value-here' });
+    const faro = FaroHelper.initializeFaro();
+    expect(faro).toBeUndefined();
+  });
+
+  test('It skips initializing if values are missing', () => {
+    let faro;
+
+    process.env = getProcessEnv({ faroUrl: undefined });
+    faro = FaroHelper.initializeFaro();
+    expect(faro).toBeUndefined();
+
+    process.env = getProcessEnv({ apiKey: undefined });
+    faro = FaroHelper.initializeFaro();
+    expect(faro).toBeUndefined();
+
+    process.env = getProcessEnv({ enabled: undefined });
+    faro = FaroHelper.initializeFaro();
+    expect(faro).toBeUndefined();
+  });
+});
diff --git a/grafana-plugin/src/utils/faro.ts b/grafana-plugin/src/utils/faro.ts
index 34a13ba1..7cec49c0 100644
--- a/grafana-plugin/src/utils/faro.ts
+++ b/grafana-plugin/src/utils/faro.ts
@@ -28,7 +28,7 @@ class FaroHelper {
     };
 
     if (!faroConfig?.enabled || !faroConfig?.url || !faroConfig?.apiKey || this.faro) {
-      return;
+      return undefined;
     }
 
     try {
@@ -58,6 +58,8 @@ class FaroHelper {
 
       this.faro.api.pushLog(['Faro was initialized for Grafana OnCall']);
     } catch (ex) {}
+
+    return this.faro;
   }
 }